Connected things, which are presented as being “the Internet third revolution” are now becoming increasingly prevalent in all fields of daily and corporate life. Most of these things are intended for the production of data through their integrated sensors in order to give value-added services to their owners.
The very applications concerned are such that these connected things are mainly nomadic things. In particular, they should be capable of transmitting data produced regularly or at request to a distant user.
To this end, long-range radio transmission of the mobile cellular radio type (2G/3G/4G, etc.) has been a technology of choice. This technology has indeed made it possible to benefit from efficient network coverage in most countries.
However, the nomadic aspect of these things is often accompanied a need for energy autonomy. Now, even when based on the most energy-efficient mobile cellular radio technology, these connected things presently show consumption levels that rule out large-scale deployment at reasonable costs.
Faced with the problems of consumption by radio links for such nomadic applications, novel low-consumption radio technologies and low-bit-rate radio technologies, specifically dedicated to the “Internet of Things” networks, i.e. radio technologies for networks known as LPWAN (low-power wide-area networks), are now appearing.
In this context, two types of technologies can be distinguished:                on the one hand, there are proprietary technologies such as for example the technology of the company Sigfox®, or the LoRa® technique or again the technology of the firm Qowisio®. In practice, these non-standardized technologies all rely on the use of the “industrial, scientific and medical” (or ISM) frequency band and on the regulations associated with its use. The value of these technologies is that they are already available and enable the rapid deployment of networks on the basis of limited investment. In addition, they enable the development of connected things that are highly energy efficient and at low cost;        on the other hand, there are several technologies promoted by standardizing organizations. For example, we can cite three technologies that are being standardized with the 3GPP (3rd Generation Partnership Project): NB-IoT (Narrow Band-Internet of Things), LTE MTC (Long Term Evolution-Machine Type Communication) and EC-GPRS (Extended Coverage-General Packet Radio Service). However, such solutions are not as yet entirely specified and will furthermore rely on licensed frequency bands.        
In this context, it can be seen that proprietary technologies based on the use of the ISM band are seen as solutions of choice in the short term and one or more of them can then actually become prevalent as the solution to be used.
For example, the patent document EP 2 449 690 B1 describes a technique of information transmission based on the modulation of a basic chirp signal on which the LoRa® technology is based.
Now, certain operators such as Bouygues® or Orange® in France, have already taken to the LoRa®technology to deploy their networks dedicated to connected things. However, initial feedback indicates unsatisfactory user experience related to low performance of the radio link in real conditions.
There is therefore a need to improve the performance of a receiver implementing the LoRa® technology in real conditions, and especially in the face of a radio mobile propagation channel that presents fading phenomena.
There is also a need that such an improvement should not lead to excess energy consumption by the receiver and should therefore not penalize the autonomy of the connected thing embedding such a receiver.